Elevator-door-opening mechanism



Dec. 8, 1925 1,564,

F. F. BRUSH ET AL ELEVATOR DOOR OPENING MECHANISM Filed April 25, 1923 5 Sheets-Sheet 1 Dec. 8, 1925. 1,564,521

F. F. BRUSH ET AL ELEVATOR DOOR OPENING MECHANISM I Filed April 25 1923 5 Sheets-Sheet 2 I I I Azwzz mwa D8C- 8, F. F. BRUSH ET AL ELEVATOR DOOR OPENING MECHANISM Filed April 5. 1923 5 Sheets-Sheet 5 firm/twins.

F. F. BRUSH ET AL ELEVATOR DOOR OPENING MECHANISM Dec. 8 1925- Filed April 25. 1923 5 Sheets-Sheet 4 Dec. 8 1925- 5 F. F. BRUSH ET AL ELEVATOR DOOR OPENING MECHANISM Filed April 1923 5 Sheets-Sheet 5 flvwswroras: FREDE/P/CKEBRUSH,

Patented Dec. 8, 1925.

UNITED STATES 1,564,521 PATENT OFFICE.

FREDERICK F. BRIJSI-I AND LUTHER E. GROAT, OF LOS ANGELES, CALIFORNIA, AS-

SIGNOBS- TO ELEVATOR SAFETY APPLIANCE (10., OF LOS ANGELES, CALIFORNIA, A

CORPORATION OF CALIFORNIA.

ELEVATOR-DOOR-OPENING MECHANISM.

Application filed April 25, 1923. Serial No. 634,475.

To all whom it may concern:

Be it known that we, FREDERICK F. BRUSH, and LUTHER E. GROAT, both citizens of the United States, and both residing at Los Angeles, in the county of Los Angeles and State of California, have invented a new and useful Improvement in Elevator-Door- Opening Mechanism, of which the following is a specification.

' Our invention relates to devices for opening the doors of elevators used in transporting people and things from floor to floor in buildings It further relates to such devices in which the operating mechanism for the doors is carried on the car.

An object of the invention is to provide members projecting from the car for operating the door, which members are so constructed that they may be pushed back inside the clearance line of the car withoutinjury thereto.

A further object of the invention is to provide on the car a positive means for locking the door at the end of the closing stroke.

A still further object of the invention is to provide means for controlling the operation of the door so that the door cannot be opened except when the car is at or very near a predetermined level, said level being determined magnetically.

A still further object of the invention is to provide means by which the door can be left open in the event the operator leaves the car, means being provided whereby the door is automatically closed in case the car accidentally moves from its position while the operator is absent.

A still further object of the invention is to provide means for interrupting the circuit to the elevator motor in case there is an excess pressure exerted tending to prevent the closing of the door.

A further object of the invention is to provide means by which the door must be closed and locked before it is possible to energize the elevator motor.

A still further object of the invention is to provide a lock which is positively actuated by the mechanism on the elevator car both to unlock and to lock the door, no dependence being placed upon springs, weights or power carried on the building structure.

A further object is to provide means by which the elevator control system interlocks and is interlocked by the locking and unlocking of the door so that the operation of the control system of the elevator is absolutely dependent upon the proper functioning of the door and the look.

A still further object of the invention'is to provide a lock which will not become jammed due tothe pressure tending to open the door, this pressure tending to open the look without jamming under all conditions. A further object of the invention is to provide a lock which will secure the door in any one or several positions locking and unlocking positively from any of these positions. A further object of the invention is to provide an indicating light in the car automatically energized-for the information of the car operator.

A further object of the invention is to provide means by which pressure on the door which is not properly applied will fail to unlock the locking device.

A still further object of the invention is to provide a lock in which the power used to unlock is entirely independent of any pressure which may be exerted on the door.

A still further object of the invention is to provide means in an elevator car for look ing the maincontroller handle of the elevator, synchronized with a power operating door mechanism which is carried on the car.

Further objects and advantages will be made evident hereinafter.

In the drawings which are for illustrative purposes only, Fig. 1 is a side elevation of the door operating mechanism carried by the elevator car with the oil retaining plate omitted for the sake of clearness.

Fig. 2 is a partial section on a plane represented by the line 2-2 of Fig. 1.

Fig. 3 is an elevation partly in section on a plane represented by the line 3-3 of Fig. 2.

Fig. 4 is a plan view partly in section along a plane represented by the line H, Fig. 3.

Fig. 5 is a detail on an enlarged scale showing a driving finger.

Fig. 6 is a section on an enlarged scale showing a locking finger.

Fig. 7 is a section through the magnetic brake on the operating shaft.

Fig. 8 is a diagrammatic elevation showing a section through the floors.

Fig. 9 is a view of the lock and-door as seen from the hatchway.

Fig. 10 is a plan view of an interlock board and magnetic cam.

Fig. 11 is an end view of same.

Fig. 12 is a side view of same.

Fig. 13' is a diagrammatic view partly in section of the door controller in its open and latched position.

Fig. 14 is an elevation of the door lock as seen from the elevator hatchway.

Fig. 15 is a plan view of same showing the position of the driving and locking fingers.

Fig. 16 is a section on a p71 by the line 16-16 of Fig. 1

Fig. 17 is a partial section on a plane represented by the line 17--17 of Fig. 15.

Fig. 18 is a diagram of connections.

Referring particularly to Figs. 8 and 9, our invention employs a car 20 which may be lifted by a plunger 21, or which may be lifted or counter-weighted by cables 22 in accordance with either standard hydraulic ane represented or electric practice, our invention being adapted to be used with either system. Mounted on the top of the car 20 is an electrically actuated door operating mechanism 23 which will hereinafter be described at more length, and mounted on the structure of the building at 24 above each of the elevator doors 25 is a door locking mechanism illustrated in Figs. 14 to 17 inclusive, the door being operated from the locking mecha nism by means of a lever 26 pivoted at 27 on the building structure. Each of the doors 25 closes a doorway into the hatchway which registers with the doorway into the elevator car when the car is at the proper level to serve that particular floor. Mounted on the locking mechanism at each floor is a steel or iron plate forming an armature 28 which co-acts with a magnetic cam mechanism 29 which will be hereinafter explained, this cam mechanism being illustrated in Figs. 10, 11 and 12.

Mounted in the car 20 is a door controller 30, illustrated in Fig. 13 and having its internal structure shown in the diagram Fig. 18, and any type of elevator controller 31 whose parts are shown in the diagram, Fig. 18. If the elevator is electrically operated the controller 31 is utilized to control the circuits to the operating motor, and if, on the other hand, the elevator is hydraulically operated the elevator controller 31 is utilized to operate the valves controlling the water supply.

In the followin description it will be assumed that the e evator is electrically operated, having a main elevator motor which raises and lowers the car 20 through suitable mechanism 0 rating cables 22. This elevator control er 31 may be inserted in the main circuit of the motor, but it is preferides connected by end. members 41.

liding in the guides 40 is a frame 42 to which a primary cam 43 is rigidly secured. Sliding in the frame 42 is a block 44 which carries a secondary cam 45. The block 44 is forced over in the frame 42 by a compression spring 46, and a pneumatic spring bumper 47 is placed in one of the members 41 to cushion any over-travel of the door in closing. Formed on one of the guides 40 is a series of serrations 48 which may be engaged by serrations in a dog 49 pivoted at 50 in the block 44. The serrations 48 extend for a considerable distance to either side of the normal closed osition of the door so that variations in t e closing posi- 4 tion can be readily accommodated. The dog 49 is connected through a toggle, formed of links 51 and 52, with a pin 53 secured in the frame 42. An actuating link 54 connects the toggle formed of the links 51 and 52 with a pin 55 carried in the block 44. A link 56 pivoted on a pin 57 on the frame- 42 connects with the lever 26 which in turn is connected to the door 25 as has previously been explained.

The method of operation of the door lockin mechanism is as follows:

Whenever the lock is not externally restrained the sprin 46 tends to force the block 44 downward y as shown in Fig. 17 in the frame 42, this downward movement of the block 44 tending, through the member 54, to straighten out the toggle formed of the links 51 and 52 and to force the serrations in the dog 49 into engagement with the serrations 48. This separation of the members 42 and the positive locking of the door is not dependent however on the spring 46 but is further absolutely insured by'the mechanical movement of the locking fingers acting to separate the cams 43 and 45 as will hereinafter be explained. The unlocking of the door is accomplished by a pressure in the direction of the arrow A in Fi 14 against the cam 45, produced as will ereafter be explained, this movement first unlocking the door and then moving the door bodily by means of the frame 42 and its connected members including the bar 26.

For the purpose of operating the door the mechanism illustrated in Figs. 1, 2, 3 and 4 is employed. This mechanism consists of a frame 60 having a motor driven shaft 61 journaled in the top thereof, this shaft carrying a brake pulley 62 engaged by the magnetic brake shown in Fig. 7, and also having a worm 63 which engages an interrupted worm gear 64. The shaft 61 is driven by an electric motor not shown but whose armature is shown diagrammatically at 65 and whose fields areshown at 66 and 67 in the diagram, Fig. 18. An operating coil 68 for the magnetic brake shown in Fig. 7 is also shown in the diagram Fig. 18. The method of operation of the magnetic brake will be evident from the drawing and as this brake forms no portion of the present invention, it will not be described herein.

The interrupted gear 64 is rigidly secured to a shaft 70 turning in suitable bearings in the frame 60, this shaft carrying a cam plate 71 which carries a crank pin 72. The cam plate 71 has a cylindrical contour through its central portion as shown at 73, this contour being struck from the center of the shaft 70. At either end of this surface cam, surfaces 74 and 75 are formed, these cam surfaces co-operating with external surfaces 76 and 77 formed on the plate 71 to operate switches 80, 81 and 82 through cranks 83, 84 and 85 as will hereinafter be ex plained. The switches 80. 81 and 82 are utilized for interlock and limiting purposes .as will hereinafter be described.

Sliding in the frame 60 and being restrained therein by an oil retaining plate 86 isthe square base 87 of a yoke 88. Sliding vertically in the yoke 88 is a cross-head block 89 which is engaged by the crank pin 72. The top of the block 89 is beveled as shown at 90, this bevel forming a cam to operate a roller 91 carried on the closing driving finger arm 92. This driving finger arm 92 is pivoted at 93 to the yoke 88 and is connected through a link 94 with a gear 95 which turns freely on a shaft 96 secured in the yoke 88. A link 97 also connects the gear 95 with an opening driving finger arm 98 which is pivoted at 99 on the yoke 88. The arrangement of the links 94 and 97 is such that the arms 92 and 98 move simultaneously in opposite directions when actuated by the roller 91 or by a tension spring 100 which holds this roller against the block 90. It should be noted that the central line of the link 97, when in position shown in Fig. 2, is substantially coincident with the center of the shaft 96 so that the arm 98 is locked in the position shown in that figure.

Turning on a pin 101 secured in the yoke 88 is a locking pinion 102 which carries locking fingers 103 which are free, as shown in Fig. 6, to move in and out of the gear 102 against a compression spring 104 so that these fingers may be forced back into the gear in case they are engaged by the sloping shoulders of either of the cams 43 or 45. Pivoted on substantially vertical pins in the arms 92 and 98 are driving fingers 111 which carry driving rollers 112, these fingers being held in their outer position by compression springs 113, their motion being limited by stop pins 114. The function of the driving fingers 111 is to force the cams 43.

closing driving finger 111 carried by thedriving finger arm 92 is utilized to close the door, and the opening driving finger 111 carried by the driving finger arm 98 is utilized to o n the door, as will hereinafter be explaine Formed on the driving finger arm 92 and projecting outwardly therefrom is a projection 120, best shown in'Figs. 3 and 4, this projection sliding in a groove 121 in an arm 123 pivoted at 122 in the frame 60. A rod 124 is secured in this arm, this rod passing upwardly through a lever 125 pivoted at 126 on an interlock board 127. A flat spring 128 is engaged by a nut 129 on the end of the rod 124, the lever 125 having a flat strip 130 having the form shown in Fig. 1 which is adapted to be engaged by a projection 131 carried on the yoke 88. The arm 125 carries brushes which are connected together and insulated from this arm and which serve to connect members 141, the members 140 and 141 forming a switch which can be conveniently designated as switch 142. Brushes 143 are also carried in and insulated from the arm 125, these blocks connecting contacts 144, the brush 143 and the contacts 1 144 forming a switch which may be designated as switch 145. The blocks 141 and 144 are separated by an insulating member 146, the parts being so arranged that as the brush carrying end of the lever 125 moves downwardly, the switches 142 and 145 are closed, the switch 142 closing first and opening last. The function of these switches will be hereinafter explained.

Mounted in ball bearings in an extension of the frame 60 is a magnet 151 having windings 152. This magnet is provided with pole pieces 153 which are so placed that they tend to come into magnetic relationship with the plates 28 whenever the car 20 reaches the proper level to serve a particular floor. The magnet 151 extends vertically and the weight is so distributed that it tends to lean away from the plates 28, being attracted thereto in the direction of the arrow B shown in Fig. 11 whenever the magnet comes into magnetic relationship with any one of the plates 28. Carried by an handle 160 which carries a latch 161 which is normally pressed upwardly from the position shown 1n dotted lines in Fig. 13 into the position shown in full lines in that figure under the action of the compression spring 162. This latch may be pressed downwardly by means of a projection 163 by the thumb of the operator, and when pressed down it is engaged by a stationary hook 164 which is held in its upper positlon by a compression spring 165 and which is pulled downwardly magnetically by a 0011 166. When the hook 164 is pulled downwardly, the controller handle moves from the opening position shown in Fig. 13 into a closing position indicated by the line wm of that figure, a spring 167 being utilized to effect this return.

The method of connection is shown in Fig. 18 which may be considered as representing an electrically operated elevator. The current for door operating mechanism is supplied to the car through a main switch 180 through a cable 181 to a car switch 182 situated in the car. One side of the circuit, which may be conveniently designated as plus, is connected respectively to one side of the shunt field coil 66 which is connected through the coil 152 of the magnetic cam to the negative side of the circuit. The shunt field of the door operating motor is therefore always energized when the switch 182 is closed, as is also the coil of the magnetic cam. The plus side of the circuit is also connected through wires 300 and 301 to a finger 183 in the door controller 30, this finger being connected by means of the segments 184 or 185 and wires 302 or 303 with either a winding 186 or a winding 187 of reversing relays 304 and 305. The contacts of these relays are arranged to connect the armature through wires 306 and 307 in either a positive or negative direction through wires 308 and 309 in series with the series field 67 of the door operating motor and the coil 68 of the magnetic brake. The other end of the coil 186 'is connected through a wire 310 to one of the contacts 158 to which is also connected an indicating light 188, this light being used to indicate when conditions are right to open the door of the car as regards cars proper position to floor. The other side of the light 188 is connected to the positive side of the circuit through the wire 300. The other contact 158 is connected by a wire 311 through the switch with a wire 312 connected to the negative side of the circuit. The switch 80 is so arranged that it opens only when the door is wide open, closing as soon as the door starts to close, this actuation being accomplished by the cam plate 71 acting on the lever 83. The other side of the coil 187 is connected by a wire 313 through the switch 142 and a wire 314 with the switch 81. The switch 142 is opened in the event that a person becomes caught in the door, so that the spring will be extended due to the pressure on the driving finger carried by the driving finger arm 92. This opening of the switch 142 is prevented by the member 130 at the time that the door is closed, so that the switch 142 is not actuated by the movement of the block 90. The switch 81 opens when the door is en tirely closed, closing as soon as the door starts to open. The other side of this switch is connected to the negative side of the circuit through the wire 312.

Threshold lights 190 are provided, these lights being energized by fingers 191 in the door controller 30, which are connected by segments 192 whenever the door cont:oller is thrown to the open position; the threshold lights, under these circumstances, being connected through the wires 300 and 301, and a wire 315 with the plus side of the circuit and through a wire 316 and the wire 312 with the negative side of the circuit. The coil 166 on the door controller 30 is connected in series with the switch 157 which is closed at all times that the magnetic cam is not in magnetic relationship with the plate 28, this switch being opened whenever the car reaches the proper level at the floor, thus opening the circuit to the coil 166. This coil is, however, connected through a wire 317 to one of the fingers 193, the circuit between these fingers being closed through segments 194 only when the door controller 30 is in the opening position. The closing of this circuit connects the coil 166 to the .negative side of the circuit through a wire 318, the switch 157 being connected to the plus side by a wire 319 and the wire 300.

The main elevator control circuit is supplied from the plus side of the circuit through the wire 300 and through a wire 200 which connects to the switch 82. This switch is closed only when the door is shut and locked, being opened at all other times. The switch 82 is connected by a wire 320 in series with the switch 145 which is carried on the arm 125, this switch also being opened in the event that anyone is caught in the door, thus extending the spring 100 due to throwing the driving finger arm 92 in a counter-clockwise direction as viewed in the various figures. If the switch 82 and the switch 145 are closed, the finger 210 on the door controller is energized through a wire 321, this fin er being connected to a similar finger 211 t rough segments 212 when the controller is in the closing position. The finger 211 is connected to the elevator control circuit through a wire 214. This control circuit is fed through wires 213, the main controller of the elevator (not shown) being supplied with current from the negative side otthe circuit through a wire (not shown).

When the switch 82 and the switch 145 are closed there is an auxiliary circuit from the plus side of the circuit through the wire 300, the wire 200, the switch 82, the wire 320, the switch 145 and a wire 325, through a coil 220 shunted by an indicating lamp 221 to the negative side of the circuit through the wire 312. When the coil 220 is energized a lock 222 is withdrawn against the action of a spring 223, allowing the handle 224 of the elevator controller 31 to be actuated. Whenever this coil 220 is not energized the handle 224 is locked in the oil position. The handle. 224 is normally provided with. a spring, not shown, tending to throw it back to the otf position, if it is released, where it may be locked by the lock 222.

The method of operation is as follows: Assuming that all the doors are closed and locked and that the car 20 is approaching a floor, it will be seen that previous to the time that the cams 45 pass between the driving finger rollers 112, it is mechanical- 1y impossible to operate the door from the car as there is no mechanical connection. The door is locked by the dog 49 engaging the serrations 48. During the time that the elevator is operating between floors, the magnetic cam is in'what may be termed its retracted position, the switch 158 being open and the switch 157 being closed. The coil 186 of the door opening relay thus has its circuit interrupted so that itis impossible to actuate the armature 65 in a direction which will open the door. Whenever the car reaches a floor, the magnet 151, acting on the plate 28, closes the switch 158 and opens the switch 157 which allows the operator to open the door if he so desires. The closing of the switch 158 energizes the light 188 thus indicating to the operator that he can open the door by means of the door controller 30.

If, when the car arrives at what may be tcrmined the normal zone at any floor, that is to say, with the floor of the car. within a predetermined distance of the floor of the building as determined by magnetic cam proportions, the operator wishes to open the door, he moves the door controller '30 into the opening position, throwing the segments 184, 192 and 194 into action. This movement of the door controller completes the circuit through the relay 186 through the switch 158 and through the switch-80 which is closed at that time. The operation of the. relay 186 due to the closing of its circuit by the segments 184 closes the circuit through the armature 65 in the proper direction to open the door. This opening 1 and 3. The initial movement of the cam plate 71 opens the switch 82 and closes the switch 81. The opening of the switch 82 opens the circuit through the coil 220, thus looking the main elevator controller 31 in its off position. It also interrupts the main elevator circuit to the positive side of the circuit through the switch 145 and at the finger 210, this finger supplying the main controller through the segments 212 only when the door controller 30 is thrown to the closing position.

In the event that the operator should throw the controller 30 to the closing position with the door partly open, it will still be impossible to supply current to the main elevator control system due to the fact that the switch 82 is open. The switch 82 serves as a positive interlock therefor to provide for opening the main elevator controller circuit at all times except when the door is closed and locked. It should be understood that thedoor controller 30 is normally in the closing position due to the action of the spring 167, this being the normal condition of the controller 30 when the car is operated. If for any reason the operator throws the door controller 30 from the ofi' position, the main circuit is interrupted at the fingers 210 and 211 positively and quite regardless of any other conditions which may exist. There is therefore a positive interlock in the door controller which opens the main elevator control circuit if at any time the door controller is thrown from the closing position.

As the cam plate 71 is rotated at the beginning of its motion, forcing the block 90 downwardly, the roller 91 slides over the inclined top of the block 89 under the influence of the spring 100, and the driving finger rollers 112 are pulled inwardly thus closing down on the outer surfaces of the cams 43 and 45. This forces these cams together, unlocking the door as has previously been explained, and the door is then opened by the continued movement of the yoke 88, the force of which is trans mitted through the driving finger to the primary cam 45.. Just before the door reaches its fully open position, the switch 80 is opened thus interrupting the circuit through the door opening relay 186 which drops, thus opening the circuit to the motor 65 and stopping the device.

If the operator now desires to leave the car, he pushesthe latch 161 down until it hooks over the hook 164, thus locking the door controller 30 in the opening osition. If for any reason, such as leaky va ves in a hydraulic elevator, the car moves up or down it soon reaches a position where the magnet 151 is out of magnetic relationship with the plate 28. The primary cams 43 are cut of sufficient length to insure the magnetic cam operating before the rollers 112 are driven oil from the cams 43 and 45. Whenever the magnetic cam reaches a position where it is released from the plate 28, the switch 158 is opened and the switch 157 is .closed. The closing of the switch 157 energizes the 0011 166 through the fingers 191, this coil 166 pulling downwardly on the hook 164, thus releasing the hatch 161 which allows the handle 160 to be pulled into the closing po-' sition m-m by means of the spring 167. This has exactly the same effect as if the controller were operated by hand, being thrown from the opening to the closing position, the movement of the door controller 30, from the opening to the closing position, breaking the circuit through the coil 166 due to opening the circuit at the fingers 193. As has been explained, the operation is exactly the same as would occur if the operator remained in the car and threw the door controller to the ofi' position, but has the advantage, that, in case such operation were brought about by stretching cables as passengers entered car, the operator could prevent the automatic action by holding handle.

In the event that the operator throws the door controller to the closing position, he establishes a circuit through the fingers 183 with the coil 187 of the door closing relay through the switch 142 and through the switch 81, which is closed at all times except when the door is completely shut. The door closing relay therefore energizes the armature 65 in such a direction that the yoke 88 is driven from left to right, the door being operated through the primary cam 43. During this time the rollers 112 are both pressed firmly against the cams 43 and 45; The door is therefore moved to close, and, as it approaches its closed position, the switch 81 opens thus interrupting the circuit through the coil 187 and allowing the door closing relay to interrupt the circuit through the armature 65. At the same time, the switch 82 closes thus allowing the main elevator control system to be reestablished and also energizing the coil 220 so that the main elevator controller is unlocked and the indicating li ht 221 is lighted showing the operator that the door is closed and locked and the main elevator controller can be operated.

As the door completes its closing motion, the block 89 moving upwardly throws the roller 91 into the position shown in Fig. 3 which forces the driving finger rollers 112 away from the cams 43 and 45. This allows the spring 46 to force the cams 43 and 45 apart tending to lock the door. For the urpose of providing a positive lock, the loc ing, fin ers 103 are rovided. As'the roller 91 is orced upwardly by the block 89 the gear 95 is rotated, this gear rotating the gear 102 and causing the pins 103 to move through an angle of nearly 180 degrees. The pins 103 project between the cams 43 and 45 and as they assume the position shown in Fig. 14, they positively force these cams apart for a distance to msure the absolute locking of the door.

With the door fully closed it is possible to operate the elevator controller 31, and as soon as the car moves for a short distance so that the magnetic cam does not co-operate with the plate 28, the switch 158 is opened which absolutely prevents the operation of the door 0 ening relay. The proportion of the parts is such that the switch 82 is not closed until after the locking fingers 103 have com leted their motion and locked the door. T e movement of the parts is also suflicient to throw the rollers 112 a suflicient distance off the primary cams to prevent these cams catching upon the rollers as the car approaches the floor. This is necessary as it is impossible to rigidly guide a car and some latitude must be allowed. In the event that the cams 43 and 45 are not in their proper position, as for example due to a manual operation of the door when the car is not at floor, resulting in an imperfect closing of the door, it will be seen that the cams 43 and 45 might possibly catch between the fingers 111 and 103. These fingers are so constructed, as shown in Figs. 5 and 6, that they will be pressed inwardly by the inclined end of the cams so that no damage will be done; to them due to this abnormal condition. 1

In the event that the door is held from closing for any reason, such for example as a person being caught in the door, the driving finger arm 92 will meet with abnormal resistance. This will extend the spring 100 and will move the projection 120 downwardly', this projection sliding in the groove 121 causing the rod 124 to be pulled down, thus actuating the arm 125 and o ening the switches 142 and 145. The opening of the switch 142 opens the circuit to the other closing relay, thus interrupting the circuit to the armature 65 and the opening of the switch 145 opening the circuit to the main elevator controller and shutting off the circuit to the main elevator motor. As a result, if anyone is caught in the door, the closing of the door is immediately stopped and any movement of the elevator is prevented. When, however, the door is entirely or almost closed, it is possible to exert pressure thereon without opening the switches. 142 and 145 connected to the arm 125, due to the fact that the arm 125 is restrained in the closing position of these switches by the engagement of the members 130 and 131, sov

" the other when said projectionsregister correctly; and means for somounting one of said projections that it may be forcedbut of the path of the other projectionjn the event that said projections fail to register cor: rectly.

2. In a door operating device for use in connection with a car moving in a structure; a car projection carried on the car; a door projection carriedon the structure; means for actuating one of said projections to move the other when said pro ections register correctly; and means for so mounting one of said'projections that it may be forced out of the path of the other projection in a direction substantially at an angle to the line of travel of said projection in the event that said projections fail to register correctly.

3. In a door operating device for use in connection with a car moving in a structure; a car projection carried on the car; a door projection carried on the structure;

mechanism carried on the car for actuating said car projection; means by which said door projection operates the door; and means for so mounting said car projection that it may be forced back towards the car in the event that the door projection strikes said car projection in improper registration.

i. Ina door operating device for use in connection with a car moving in a structure having a door sliding therein: a mechanism carried on said car; a driving finger; means by which said mechanism operates said driving finger; elastic means for holding said finger extended from said car; and a cam sliding in said structure and operating said u door, said cam being so shaped as to force said finger towards said car in the event of improper registration between said cam and said finger.

5; In an elevator, a structure having a floor; an elevator moving to and away from said floor; a door operating mechanism carried on said car; a floor level deteri'nining device for inhibiting the operation of said mechanism except when said car is in a zone within a predetermined distance from said floor; and means by which said mechanism can move said door even when said car is considerably outside said zone.

6. In an elevator: a car; a building structure in which said'car moves; a door openmg mechanism carried on the car; means for inhibiting the operation of said mechanism; a ferrous member carried on said car forming a portion of a magnetic circuit; a ferrous member carried on said structure and so placed as to complete said magnetic circuit when said car is at or near a floor; means for energizing said magnetic circuit; and parts so constituted as to remove said inhibition from said mechanism upon the completion of said circuit.

7. In an elevator: a car; a building structure in which said car moves; a door openmg mechanism carried on the car; means for inhibiting the operation of said mecha-- circuit when said car is at or near a floor;

means carried on said car for energizing said magnetic circult; and parts so constituted as to remove said inhibition from said mechanism upon the completion of said circuit.

8. In an elevator: a car; abuilding structure in which said car moves; a door opening mechanism carried on the car; means carried on said car for inhibiting the operation of said mechanism; a ferrous member carried on said car forming a portion of a magnetic circuit; a ferrous member car-' ried on said structure and so placed as to complete said magnetic circuit wnon said car is at or near a floor; means for energizing said magnetic circuit; and parts so constituted as to remove said inhibition from said mechanism upon the completion of said circuit.

9. Inan elevator: at car; a building structure in which said car moves; a door open ing mechanism carried on. the car; means carried on said car for inhibiting the operation of said mechanism; a ferrous member carried'on said car forming a portion of a magnetic circuit; a ferrous member carried on said structure and so placed as to complete said magnetic circuit when said car is at or near a floor; means carried on said car for energizing said magnetic circuit; and parts so constituted as to remove said inhibition from said mechanism upon the completion of said circuit.

10. In an elevator door operating device: a mechanism for operating the door; a door controller for controlling said mechanism;

spring means for throwing said controller to the closing position unless restrained; a latch for holding said controller in the opening position; releasing means for disengaging said latch; and means operated by the movement from the floor in either direction for actuating said releasing means.

12. In an elevator: a car; a building structure; a door sliding in said structure; a projection sliding with relation to said structure; means by which said projection opens and closes said door; two fingers carried on said car one for opening and one for closing said door; mechanism for forcing said fingers together to contact with said projection before moving same; operating mechanism for sliding said fingers to move said projection; a flexible member through which said operating mechanism drives said closing finger; and means for rigidly locking said opening finger to said mechanism in its operative position.

13. In combination in an elevator: a car moving in a hatchway past a floor; a door moving in a fixed path to close an opening into said hatchway at said floor; means for locking said door in any of a number of positions within the limits of a closed zone; and mechanism on said car for positively actuating said means to both, lock and unlock said door.

14. In combination in an elevator: a car moving in a hatchway past a floor; a door moving in a fixed path to close an opening into said hatchway at said floor; means for locking said door in any of a number of positions within the limits of a closed zone; and mechanism independent of the motion of the car on said car for positively actuating said means to both look and unlock said door.

15. In combination in an elevator: a car moving in a hatchway past a floor; a door moving in a fixed path to close an opening into said hatchway at said floor; a power operated device on said car for closing said door; a lock for said door, said lock being arranged to lock said door in any of a number of positions within the limits of a closed zone; and mechanism by which said device positively actnates said lock to both look and unlock said door.

16. In combination in an elevator: a car moving in a hatchway past a floor; a door moving in a fixed path to close an opening into said hatchway at said floor; a power operated device on said car for closing said door; a lock for said door; two members associated with said lock which may be relatively displaced to actuate said lock; and mechanism by which said device so displaces said members.

17. In combination in an elevator: a car moving in a hatchway past a floor; a door moving in a fixed path to close an opening into said hatchway at said floor; a power operated device on said car for closing said door; a lock for said door; two members which may be relatively displaced to actuate said lock; and mechanism by which said device positively displaces said members.

18. In an elevator: a structure; a car moving in a hatchway in said structure; a door sliding to close a doorway in said structure; a lock for locking said door in said structure, said lock being arranged to lock said doorin any of a number of positions within the limits of a closed zone; members projecting into said hatchway for positively actuating said lock; and power operated means carried on the car for actuating said members to both look and unlock said door.

19. In an elevator: a structure; a car moving in a hatchway in said structure; a door sliding to close a doorway in said structure; a lock for locking said door in said structure; and key means carried on said car for positively locking said lock.

20. In an elevator: a structure; a car moving in a hatchway in said structure; a door sliding to close a doorway in said structure; a lock for locking said door in said structure; and key means carried on said car for positively locking said look, only when said car is at or near a predetermined level.

21. In an elevator: a structure; a car moving in a'hatchway in said structure; a door sliding to close a doorway in said structure; a lock for locking said door in said structure; and key means carried on said car for positively locking said lock, said key and said members being so constructed that said key clears said members after looking.

22. In an elevator: a car; driving mechanism for moving said car; a door closing an opening into said car; means for closing said door; spring means through which said door is closed; and means for inhibiting the operation of said driving mechanism whenever the force exerted on said spring exceeds a predetermined maximum.

23. In an elevator: a car; a signal in said car so placed as to indicate to an operator in said car; and means for energizing said signal whenever said car is at or within a predetermined distance from a floor.

2 1. In an ele ator: a car; a door for said car; a signal in said car so placed as to indicate to an operator when said door is posi tively closed and locked; and means for e11- ergizing said signal only when said door is so closed and locked.

In testimony whereof, we have hereunto set our hands at Los Angeles, California, this 21st day of March 1922.

FREDERICK F. BRUSH. LUTHER E. GROAT. 

